View Javadoc
1   /*
2    * Copyright (C) 2016, Christian Halstrick <christian.halstrick@sap.com>
3    * and other copyright owners as documented in the project's IP log.
4    *
5    * This program and the accompanying materials are made available
6    * under the terms of the Eclipse Distribution License v1.0 which
7    * accompanies this distribution, is reproduced below, and is
8    * available at http://www.eclipse.org/org/documents/edl-v10.php
9    *
10   * All rights reserved.
11   *
12   * Redistribution and use in source and binary forms, with or
13   * without modification, are permitted provided that the following
14   * conditions are met:
15   *
16   * - Redistributions of source code must retain the above copyright
17   *   notice, this list of conditions and the following disclaimer.
18   *
19   * - Redistributions in binary form must reproduce the above
20   *   copyright notice, this list of conditions and the following
21   *   disclaimer in the documentation and/or other materials provided
22   *   with the distribution.
23   *
24   * - Neither the name of the Eclipse Foundation, Inc. nor the
25   *   names of its contributors may be used to endorse or promote
26   *   products derived from this software without specific prior
27   *   written permission.
28   *
29   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
30   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
31   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
34   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
35   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42   */
43  package org.eclipse.jgit.lfs;
44  
45  import java.io.IOException;
46  import java.nio.file.Files;
47  import java.nio.file.Path;
48  
49  import org.eclipse.jgit.lfs.lib.AnyLongObjectId;
50  import org.eclipse.jgit.lfs.lib.Constants;
51  import org.eclipse.jgit.lib.Repository;
52  
53  /**
54   * Class which represents the lfs folder hierarchy inside a {@code .git} folder
55   *
56   * @since 4.6
57   */
58  public class Lfs {
59  	private Path root;
60  
61  	private Path objDir;
62  
63  	private Path tmpDir;
64  
65  	/**
66  	 * Constructor for Lfs.
67  	 *
68  	 * @param db
69  	 *            the associated repo
70  	 *
71  	 * @since 4.11
72  	 */
73  	public Lfs(Repository db) {
74  		this.root = db.getDirectory().toPath().resolve(Constants.LFS);
75  	}
76  
77  	/**
78  	 * Get the LFS root directory
79  	 *
80  	 * @return the path to the LFS directory
81  	 */
82  	public Path getLfsRoot() {
83  		return root;
84  	}
85  
86  	/**
87  	 * Get the path to the temporary directory used by LFS.
88  	 *
89  	 * @return the path to the temporary directory used by LFS. Will be
90  	 *         {@code <repo>/.git/lfs/tmp}
91  	 */
92  	public Path getLfsTmpDir() {
93  		if (tmpDir == null) {
94  			tmpDir = root.resolve("tmp"); //$NON-NLS-1$
95  		}
96  		return tmpDir;
97  	}
98  
99  	/**
100 	 * Get the object directory used by LFS
101 	 *
102 	 * @return the path to the object directory used by LFS. Will be
103 	 *         {@code <repo>/.git/lfs/objects}
104 	 */
105 	public Path getLfsObjDir() {
106 		if (objDir == null) {
107 			objDir = root.resolve("objects"); //$NON-NLS-1$
108 		}
109 		return objDir;
110 	}
111 
112 	/**
113 	 * Get the media file which stores the original content
114 	 *
115 	 * @param id
116 	 *            the id of the mediafile
117 	 * @return the file which stores the original content. Its path will look
118 	 *         like
119 	 *         {@code "<repo>/.git/lfs/objects/<firstTwoLettersOfID>/<remainingLettersOfID>"}
120 	 */
121 	public Path getMediaFile(AnyLongObjectId id) {
122 		String idStr = id.name();
123 		return getLfsObjDir().resolve(idStr.substring(0, 2))
124 				.resolve(idStr.substring(2, 4)).resolve(idStr);
125 	}
126 
127 	/**
128 	 * Create a new temp file in the LFS directory
129 	 *
130 	 * @return a new temporary file in the LFS directory
131 	 * @throws java.io.IOException
132 	 *             when the temp file could not be created
133 	 */
134 	public Path createTmpFile() throws IOException {
135 		return Files.createTempFile(getLfsTmpDir(), null, null);
136 	}
137 
138 }